Kthread：将结构传递给函数

Question

I'm trying to implement a kthread that needs to work with a thread.

I try to pass the struct like this which causes an error at compile time:

    int thread_function(void* data)
{
    killStruct obj = (killStruct) data;
    //msleep((unsigned int) time);
    printk(KERN_INFO"From the inner Thread: PID: %d, Time:%ld\n",obj->pid,obj->millisecondsToKill);
    //kill prozess by ID
    return 0;
}

static void prozess_kill(struct killStruct obj)
{
    task = kthread_run(&thread_function,(void*)obj ,obj->pid);
}

What is the correct way to pass a struct to such an function pointer

Answer 1

You are casting the whole struct to a void pointer, which will not work. You have to have pointer pointing to a valid struct and then pass that pointer, instead of a whole struct.

{
    struct killStruct* o = initializethestruct(); //malloc, set members

    prozess_kill( o ) ;
}

static void prozess_kill(struct killStruct* obj)
{
    task = kthread_run(&thread_function,(void*)obj ,obj->pid);
}


int thread_function(void* data)
{
    struct killStruct* obj = (struct killStruct*) data;
   ....

You also used the struct name in two different ways, it should be always struct killStruct or if it is a typedef then always killStruct .

Answer 2

将数据指针强制转换为KillStruct *类型，然后取消引用以获得Killstruct对象。

 killStruct obj = *(killStruct *)data;